1. Field of the Invention
The present invention relates to a technique to control equipment, and more particularly to a remote control system over a network.
2. Description of the Background Art
As to what is called a remote control device for controlling an operation of equipment, a remote control device permitting external manipulation over the network in addition to manipulation on hand has been known. The remote control device permits manipulation by a user holding the remote control device, that is, the manipulation on hand, and the manipulation based on control data obtained by reception of a signal transmitted via the Internet (hereinafter, referred to as “external manipulation”). Here, if the manipulation on hand and the external manipulation are simultaneously performed, the problem arises as to on which manipulation control should be based.
As to the technique for externally controlling equipment, for example, Japanese Patent Laying-Open No. 2003-198745 discloses a technique to prevent change of an operation state of equipment used in a house when the control of electrical appliances in the house is attempted by using a portable communication terminal to access a system.
In addition, Japanese Patent Laying-Open No. 2002-291057 discloses a remote control device with improved security as well as suppressed cost.
Moreover, Japanese Patent Laying-Open No. 2000-032153 discloses a remote control system eliminating restriction on positions where home appliances and a control console are placed.
According to the technique disclosed, for example, in Japanese Patent Laying-Open No. 2003-198745, however, if presence or absence at home is not sensed by a human-sensing sensor, the control based on external access is possible. Accordingly, while a user who was not sensed by the sensor for some reasons is manipulating the remote controller, input of an external signal may be accepted. In that case, the manipulation (selection of channel 200) different from the manipulation intended by the user (for example, selection of channel 100 on television) may be performed.